The Chinese language and some other Oriental languages are written in characters which are composed of a number of strokes of varying sizes and positions within each character. In contrast with languages such as English and other European languages which employ alphabets having a small number of letters, Chinese language characters are not readily disassembled or reassembled. The complete Chinese vocabulary contains approximately 15,000 different words, although only 4,000 to 8,000 words are necessary for normal communication. Thus, typing and printing this large number of individual characters poses unique problems and is extremely difficult.
Methods for mechanizing Chinese typing and printing have been developed based on several different techniques. In one approach, the individual strokes used in writing a Chinese character are each typed in the sequence in which they would be written. While a relatively small number of keys are necessary to represent these basic strokes, a large number of strokes are required for designating each character due to the complexity of most Chinese words. Another approach at the other extreme from the single stroke approach employs individual keys for each character. Since over 4,000 characters are needed for general communication, these machines are large and require a great deal of operator training. In a third approach, a set of word-roots are defined as sub-structures of Chinese words. In addition, a set of control symbols are used to denote the relative positions and connectivity between the word-roots. While this approach results in a manageable keyboard and reasonable efficiency, a great deal of operator training is necessary.